Latch for automatic dumping vehicles



M 193 5 H.W. SANFORD 2,001,471

LATCH FOR AUTOMATIC DUMPING VEHICLES Filed Dec. 5, 1952 s Shets-Sheet 1 May 14, 1935. H. w. SANFORD LATCH FOR AUTOMATIC DUMPING VEHICLES '3 Sheets-Sheet 2 Filed Dec. 3, 1932 gwwmtoz nford.

May 14, 1935. H. W.'$ANFORD LATCH FOR AUTOMATIC DUMPING VEHICLES Filed Dec. 5, 1952 3 Sheets-Sheet 3 Patented May 14, 1935 UNITED STATES PATENT OFFICE LATCH FOR. AUTOMATIC DUMPING VEHICLES 15 Claim.

This invention relates to a latch apparatus for preventing the dumping of the load of an automatic dump vehicle, which is adapted for operation at a predetermined point for the release of the load.

One feature of the present invention is the provision of such a latching apparatus with means to prevent accidental or inadvertent dumping at an undesired point.

Another feature of the present invention is the provision of latching means cooperable with two latch release devices located at the predetermined point for dumping, which cooperate at this point by causing a double energization of the latch releasing structure.

A further feature of the present invention is the provision of a latch apparatus in which the latch may be moved through certain predetermined limits without release of the latch, but which upon further movement operates to release the latch, this further movement only being imparted by the coincidence of operation of a plurality of external operators.

Still another feature of the present invention is the provision of a latch apparatus including a single latch controlling bar which may be engaged intentionally or accidentally at one point thereof without causing a release of the latch: and which must be actuated at a predetermined plurality of points-in order to produce actuation of the latch.

Illustrative forms of practicing the invention are set forth on the accompanying drawings, in

which:

Figure 1 is a longitudinal vertical section showing the application of the present latch apparatus to a vehicle which is illustrated as being a bottom dump mine car.'

Figure 2 is an end elevation of the same.

Figure 3 is a longitudinal vertical section corresponding to Fig. 1, but showing the latch released, and the doors moving toward a preparatory dumping position.

Figure 4 is a section corresponding to Fig. 3 but showing one of the doors releasing its load.

Figure 5 is a detail view on a larger scale of a housing member for the latch assembly.

Figure 6 is a detail view showing the relationship of this housing to the latch elements.

Figures 7 and 8 are face and side elevations of a latch piece.

Figures 9 and 10 are face andside elevations of a latch reinforcing element.

Figures 11 and 12 are views, on a larger scale, of a modified form of latch, shown in longitudinal vertical section.

Figure 13 is a similar view of a further modified form of latch.

In these drawings the invention is shownillustratively as applied to a mine car of the bottom dump type having a plurality of bottom dump doors which are secured in transport position by their interengagement and by the securing of the rear door by a latch apparatus of the present type. This latch apparatus is intended to be released at a predetermined dumping point by the conjoint action of a plurality of releasing devices located along the right of way, so that the said rear door is thus released preparatory to dumping, and in turn this rear door enables the successive release of the forward doors: While the car is in transit, accidental or inadvertent movement of the latch releasing structure for example at a point which it cooperates with one of the plurality of actuating devices does not lead to the release of the latch, and further, for example, the contact of the releasing structure with lumps of coal, mine timbers or other obstacles does not cause a false" dumping along the right of way.

The car is illustrated as having a body comprising side walls IO, end walls H, l2, axles l3, wheels l4 and a plurality of bottom dump doors l5, l6, H. The front bottom dump door I5 is mounted on a fixed pivot I 8 and extends at its rear edge so that it rests in transport position (Fig. 1) upon the forward edge of the next rearward door Hi. In the illustrated form, this next rearward door It has a downwardly and backwardly folded portion formed from its sheeting to engage a pivot l9 extending transversely between the side walls, so that it may both pivot and slide with respect thereto: this middle door l6 likewise has its rear edge extending over and resting upon the forward edge of the rear door ll while in transport position. The rear door ll likewise has a downwardly and rearwardly folded portion engaging a transversely extending pivot member l9 so that it may swing and slide with respect thereto: the rear door l1 has its rearward edge supported by the downwardly and forwardly inclined shelf 20 of a pivoted latch member 2| which fits over a transversely extending latch pivot 22.

In the illustrated form, the middle and rear doors l6, l1 have parts which engage during their closing movement with fixed wedging members 23 usually located adjacent and secured to the side walls l0, so that these doors 6 and I1 are forced bodily forward relative to the side walls III toward the end of their closing movement, resulting in a sliding of the doors with respect to their pivots l9 into the aforesaid overlapping and interengaging position as shown in Fig. 1. These fixed cam pieces 22 likewise serve to prevent relative rearward sliding movement of these doors while in transport position, so that all doors are held in load-containing position by the single latch shelf 20.

On the end wall |2 of the car are provided the guide straps 25 which have their intermediate portions spaced from the end walls and serve to prevent longitudinal movement of a transverse latch actuating bar 26 relative to the car body, while permitting it to be rocked or to be raised bodily. As shown in Fig. 2, ,a vertically sliding latch control member 21 is secured by a pivot 28 to the latch actuating bar 26 at an intermediate point of its length. The projecting ends 26a of the bar 26 extend laterally beyond the lading walls of the car body so that they may be engaged by the latch releasing devices D located at a predetermined point along the right of way (Figs. 2 and 3).

The vertically slidable member 21 may be bent and ofiset as shown at 21a in Fig. 6 to pass within the bumper and coupler structure, and is provided at its lower end with an inwardly extending portion 211; which serves as the latch control piece. The latch member 2| preferably is formed of plate material, and extends from side to side of the car to furnish a ledge 20 for affording ample support to the rear edge of the rear door l1, being stiffened from point to point by the reinforcing pieces 22 (Figs. '1, 9 and 10), which likewise prevent any upward movement of this latch member with respect to its pivot 22. Centrally of the car the latch member is cut away for the reception of a latch control element 2| (Figs. 6, '1 and 8) which has perforated lateral ears 22 by which it may be rigidly secured to the latch member 2|, these ears extending between the two arms of the U formed by the-latch member 2| and serving to reinforce the same adjacent the cutaway point. This latch control element 2| has a central wall 22 which is vertical when the latch is engaged (Fig. 6) and is provided adjacent its upper end with an angularly disposed wall 24 (Figs. 6 and 8) located above the axis of the latch pivot 22, and this element 2| terminates at the top in a reversely inclined wall 26. Lateral flanges 26 are preferably provided for assisting in guiding the vertical movement of the latch control element 21b which is thus presented by the vertically sliding member 21 between the inward wall of the end structure 13 and the aforesaid fiat surface 22, and thus blocks any clockwise swinging movement of the latch member 2| so long as the element 21b is below the axis of latch pivot 22.

The latch structure is preferably protected against contact by the lading of the car by a housing 21 (Fig. 5), which may be formed as a casting and secured inside the end wall l2 which is suitably cut away at this point to afford free vertical movement for the latch control element 21, this housing 31 extending downwardly substantially to the latch member 2|.

The end structure B carries two supporting blocks 40 (Fig. 2) upon which the bar 26 rests while in its lowermost position.

While the car is in loaded condition, with the doors in the latched position shown in Fig. 1, no engagement of either end 260 of bar 26 will cause a release of the latch and thus a dumping of the car. If the left-hand end 2211 (Fig. 2) is raised (dash and double dot lines), the bar swings about the right-hand support block 40 and the pivot pin 28 is raised only a short distance. The verticallysliding member 21 is raised a corresponding distance, but its control element 21b still remains below the axis of latch pivot 22, and hence in blocking position for preventing the clockwise movement of latch 2|. Thus, the latch is not released by such inadvertent or accidental movement of either end ofthe bar 26.

Upon arriving at the predetermined dumping point, however, the trackside ramps D (Figs. 2 and 3) engage both ends 2611 of bar 26, and by their conjoint action the bar is raised bodily (Fig. 2, dotted line position), thus raising the sliding control element 21 and its control piece 21b until the latter is above the latch pivot 22, so that the latch 2| is now free to swing in a clockwise'direction (Fig. 6). The continued upward movement of the control element 21b brings the latter into engagement with the surface 24, and causes a positive clockwise swinging of the latch into door-releasing position, and ultimately the element 211) comes to rest over and against the surface 26 (Figs. 3 and 4) in which the latch 2| is held in a rocked position, so that the rear door I1 is not obstructed in its return movement. This clockwise movement of the latch 2| has released the rear door |1 so that the latter may fail downward under the weight of its load.

By its weight and lading, and under the endwise pressure given to this rearward door by the action of the middle door l6 thereon, and by the dragging of this door upon the right of way, this rear door slides relatively rearward with respect to its pivot I! (Fig. 3) so that it in turn releases the middle door I, and this in turn may release the front door II. The doors are thus freed to fall to the right of way, but owing to clearances, no substantial part of the load is thus discharged, but the lading continues forward with the car over a dumping point which is shown in Figs. 3 and 4 as comprising a hopper located between the rails. As each door comes to an unfilled part of the hopper it may move farther downward at its rear edge to release its load, so that the lading is gently deposited in the hopper by the doors as they successively come to such an empty point (Fig. 4).

The doors are thereafter engaged by rails C located between the track rails, and thus are individually and successively raised into their closed positions. The front door I6 is swung upward substantially in the position shown by Fig. 1. The middle door I 6 is then swung upwardly, and as it passes toward its position shown in 'Fig. 1, the engagement with the fixed wedging member 22 causes a relatively forward bodily movement of this door into the former overlapping and interengaging position as shown in Fig. 1. The rear door I1 is similarly raised and moved forward into the position shown in Fig. 1.

During this time, the trackside latch operating members D have been holding the bar 26 in its raised position, but shortly after the rear door II has been raised, the trackside devices D release the bar 25 and permit it to move downwardly with its vertically sliding member 21 so that the element 21b thereof again enters into blocking. relationship between the end structure B and the flat surface 33 at a point below the axis of latch pivot 22: this action occurs while the rear door I1 is still being held in raised position by the closing rail C. It will be noted that the downward movement of sliding member 21 positively rocks the latch and its shelf 22 into holding relationship with the rear door ll.

In Figs. 11 and 12 a modified form of latch assembly is shown in which the end wall l2a has apertures near its bottom to support the pendulum pieces 50 which are connected to the latch plate 2la, which extends across the car and has a shelf 20a for supporting the rear door H. A latch actuating member 3la is connected to latch 2 la and extends outside of the rear wall l2a, being provided with a flat surface 330 which is vertical when in latching position (Fig. 11) and being joined at the top to an inclined surface 34a. These surfaces cooperate with the inwardly extending end 21c of the vertically sliding member 21. In order to compensate for any wear or inaccuracy in these parts and to cushion the operation of the parts, a blade spring 5| is secured in a groove in surfaces 33a and 34a and extends above surface 34a so that it is engaged by the projection 210 (Fig. 12) when the sliding member 21 is raised.

The operation of this construction is substantially the same as before. The positive bodily raising of bar 26 upon conjoint action of trackside rams causes an upward movement of sliding member 21 so that the portion 210 is withdrawn from its blocking position (Fig, 11) until it is above the pivot point of latch 2| 0, and comes into engagement with the spring 5| and surface a and thus positively effects a clockwise rocking of the latch 2m to release the door l1, and then is held in this position so that the latch does not interfere with the free return or closing movement of the door I! as before.

In the form of construction shown in Fig. 13, the latch 2Ib has a ledge 20b to support the rear door IT, as before, and is supported by the pendulum pieces 50a which are supported in apertures at the lower end of the end wall He. The latch 2| b is provided with an ear 52 supporting the pivot 53 of a first toggle link 54 which is joined by an intermediate pivot 55 to a second toggle link 56 mounted by pivot 51 on an ear 58 supported on the end structure B. The bar 26 is connected by a pivot 28 as before to a vertically movable member 21d. which at its lower end engages the intermediate pivot 25.

While in transport position (Fig. 13, full lines) any slight rocking movement of the bar 26 does not raise the intermediate pivot 55 to the line of centers of the three toggle pivots, and its upward movement is opposed by the resistance opposedto counterclockwise rocking of the latch 2w by the weight of the load on door H, which produces a return of the toggle elements to the position shown in full lines. When, however, the bar 26 is raised bodily, the vertical member 21 pulls the intermediate pivot 55 above the line of centers of the two outer pivots, so that the toggle rapidly collapses with an upward movement of the intermediate pivot ,55 into the dotted line position, this being effected by the aforesaid pressure of the door l1, so that the door is quickly and immediately released, and in turn may serve to release other doors.

It will be noted that in'each form of construction conjoint operation at a plurality of points is necessary for the definite release of the latch structure: and that minor movements of the latch structure, as may be occasioned by operation at less than all such plurality of points, does not lead to a release of the doors.

It is obvious that the invention is not limited solely to the form of construction shown, but that it may be modified in many ways without departing from the scope of the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. A dump vehicle including a body and a dumping door,a latch for securing said door-in closed position, a latch controlling member located adjacent the center of the width of the vehicle, and means having a plurality of parts pivotally connected to said member and exposed for conjoint operation by a plurality of elements located along the route of said vehicle for actuating said member to release said latch, said means moving pivotally relative to said member and being inoperative upon movement of less than all said parts for causing the release of said latch.

2. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, a latch controlling member, and means including an arm pivotally connected intermediate its ends to said member and having its ends exposed for simultaneous operation by a plurality of elements located at a predetermined point along the route of said vehicle for actuating said member to release said latch, said means moving pivotally relative to said member and being inoperative upon movement of less than all said ends for causing the release of said latch.

3. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, a latch controlling mechanism including a latch bar having a pivot connection adjacent its center and extending laterally beyond the lading portions of said body for conjoint operation to release said latch, and a latch controlling member attached to said pivot connections, said bar moving pivotally relative to said member and being inoperative when operated at one end only for causing the release of said latch.

4. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, and a latch controlling mechanism including a latch bar and a latch-controlling member pivotally connected-to the bar ad- Jacent the center of the latter so that .the, bar may rock about said pivot without releasing the latch, said bar operating when raised at both ends to move said member for releasing the latch.

- 5. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, a member movable between a position in which it holds the latch in securing relationship to the door and a position in which it holds the latch out of engagement with the door, and means pivotally connected to said member'and having a plurality of parts exposed for conjoint operation by a plurality of elements located along the route of said vehicle for bodily actuating said member to release said latch, said means moving pivotally relative to said member and being inoperative upon movement of less than all said parts for causing the release of said latch.

6. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, a member movable between a position in which it holds the latch in securing relationship to the door and aposition in which it holds the latch out of engagement with the door, and means 'pivotally connected to said member and having a plurality of parts exposed for simultaneous operation by a plurality of elements located at a predetermined point along the route of said vehicle for bodily actuating said member to release said latch, said means moving pivotally relative to said member and being inoperative upon movement of less than all said parts for causing the release of said latch.

7. A dump vehicle including a body and a dumping door, a latch'for securing said door in closed position and mounted for movement about a pivot axis ilxed with respect to said body, a wall fixed with respect to said body, said latch having a surface paralleling said wall below said axis and inclined toward said wall above said axis, a latch controlling member engaging said wall and said surface, and means for moving said member in a substantially vertical direction between a position where it acts between said wall and surface below said axis to prevent a rocking movement of said latch in the releasing direction and a position where it acts therebetween above said axis to prevent a rocking movement of said latch into engagement with the door.

8. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, and means for controlling said latch; said means including a vertically movable member movable between a normal position in which it acts to prevent a releasing movement of said latch and a position in which it permits such releasing movement, and a bar extending transversely of-the vehicle and pivotally connected adjacent its center to said member and adapted to be raised at both ends at a predetermined dumping point whereby to move said member into the permitting position, said bar being inoperative when raised at one end only for moving said member into the permitting position.

9. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, and means for controlling said latch; said means including a vertically movable member movable between a normal position in which it acts to prevent a releasing movement of said latch and a position in which it permits such releasing movement, and a bar extending transversely of the vehicle and pivotally connected adjacent its center to said member and adapted to be raised at both ends at a predetermined dumping point whereby to move said member into the permitting position, said bar being inoperative when raised at one end only for moving said member into the permitting position, means fixed relative to the body adjacent the member for limiting the downward movement of said bar and operating as a fulcrum for said bar when the bar is raised at one end only.

10. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, a structure fixed relative to the body and located adjacent to and spaced from the latch when the latch is in door-securing position, a latch controlling device operating when a part of said device is gravitationally held in a lower position to fill the space between said latch and structure for holding said latch in door-securing position, and means operable for raising said part into an upper position in which it does not fill said space whereby to release said device and latch from door-securing position and permit said latch to move toward said structure.

11. A dump vehicle as in claim 10, in which said device includes two connected toggle links of which one is pivoted to said structure and the other to said latch, and said means operates to raise said links adjacent their mutual connection.

12. A dump vehicle as in claim 10, in which said device includes two connected toggle links of which one is pivoted to said structure and the other to said latch, and said means is pivotally connected to said links adjacent their mutual connection, and means are provided for limiting the downward movement of said means so that the toggle links in their lower position hold the latch in securing position, and so that the raising oi said means operates to raise said links above the line joining their frames and latch pivot axes.

13. A dump vehicle as in claim 10, including yielding means interposed between said deviceand latch for holding said latch out of door-engaging position so long-as said part is in raised position.

14. A dump vehicle including a body and a dumping door, a latch for securing said door in closed position, and means for controlling said latch; said means including a vertically movable member movable between a normal position in which it acts to prevent a releasing movement of said latch and a position in which .it permits such releasing movement, and a bar extend: ing transversely of the vehicle and connected adjacent its center to said member and adapted to be raised to a predetermined dumping point whereby to move said member into the permitting position.

15. A dump vehicle including a body and a dumping door, a latch for securing'said door in closed position and means for controlling said latch including a bar extending transversely of the vehicle from side to side thereof and projecting at both sides for engaging with corresponding elements located along the route of said vehicle for bodily raising said bar, and means connected thereto adjacent the longitudinal center line of the vehicle for releasing the latch when said bar has been raised a predetermined distance at said connection.

' HUGH W. SANFORD. 

